Cancer. Just saying the word strikes fear into many of us. But what would you think if you learned that some cancers are contagious? This might sound far-fetched, but a contagious cancer is in fact what is threatening an entire species, the Tasmanian devil, Sarcophilus harrisii. But one person is leading the fight to save this iconic marsupial. In this video, researcher Elizabeth Murchison tells us what she's learning about all cancers by fighting to save the "Taz", which is critically endangered due to this unusual strain of cancer. Be forewarned: this video has some truly disturbing images of facial cancer.

Cancer geneticist Elizabeth Murchison grew up in Tasmania, the island home of the small, carnivorous marsupial known as the Tasmanian devil. In the mid-1990s, people noticed that the devils were beset with a terrible new disease -- a contagious facial cancer, spread by biting, that killed the animals just as they reached breeding age. By 2008, half the devil population of Australia had contracted the cancer and died. And as Dr Murchison says: "I didn't want to sit back and let the devils disappear."

Leading an international team at Cold Spring Harbor Laboratory, Dr Murchison worked to understand why this cancer was so virulent. Her goals were two-fold: saving the Tasmanian devil from extinction and understanding the epidemiology and genetics of how a contagious cancer works. One of the many surprises that she and her team discovered was that cancers from animals across Tasmania were genetically identical -- and were genetically distinct from their thousands of individual Taz hosts.

Currently, Dr Murchison is a Research Fellow in Medical Sciences at King's College, Cambridge, where she is using high-throughput DNA sequencing technologies to investigate the genetics and evolution of this disease, one of only three known cancers that spread contagiously.

Dr Murchison says: "This is why cancer is such a difficult disease to treat: It evolves."